The invention relates to wireless telecommunications, and, more particularly, to the association between a mobile station and directory numbers.
The use of mobile telecommunications systems, including cellular telephones and personal communications services (PCS), has seen explosive growth, particularly in the past decade. The use of mobile, or cellular, telephones has become so commonplace that it is not unusual to see people conversing on the telephone as they walk along the sidewalk, as they drive, even as they attend a concert or a play.
Conventional mobile telecommunications services employ a mobile identification number (MIN) for authentication, for termination, and for many other operations. However, the mobile identification number has proven inadequate for worldwide applications. Consequently, systems are being developed which employ an international mobile subscriber identity (IMSI) that will allow mobile telecommunications devices to operate seamlessly throughout the world. At some point, when IMSI devices are introduced there will be a mix of devices operating in the field; some mobile devices will employ a mobile identification number, some will employ an international mobile subscriber identity that is based on a more conventional mobile identification number, and some will employ xe2x80x9cpurexe2x80x9d IMSI numbers.
During the process of establishing, or xe2x80x9cterminating a telephone call (which may involve the transmission of voice, data, or both) that involves a mobile station, a wireless system associates a directory number with the identifier (MIN or IMSI). A conventional wireless system may store the mobile unit""s identification/directory number association information in the mobile unit""s home location register (HLR). Only one directory number is associated with a given mobile identifier. This restriction limits the flexibility with which a mobile unit may be used and limits the range of services a mobile telecommunications service provider may offer to an end-user.
A mobile telecommunications system in accordance with the principles of the present invention includes database entries that associate the identifier of a mobile unit, which could be a cellular telephone or a personal communications service (PCS) device, with a plurality of directory numbers. The mobile unit identifier may be a mobile identification number (MIN) or international mobile service identifier (IMSI), for example. The system may store this association within a home location register (HLR), within a mobile switching center (MSC), or in both. In the process of terminating a telephone call the system employs supplemental information to determine which of the plurality of directory numbers associated with the mobile unit""s mobile identifier is to be employed for the purposes of the telephone call being terminated. The supplemental information may be the current location of the mobile unit, for example. In such an embodiment, one directory number may be employed to terminate a telephone call within one geographic area, another directory number may be employed to terminate a telephone call within a different geographic area, and so on. Different services and prices may then be associated with each directory number, and, indirectly, with supplemental information, such as the current location of the mobile station.
The location of the mobile unit may be determined, for example, from cell and sector information located at a mobile switching, for example. Alternatively, the geographical information may be supplied to the mobile telecommunications system from a global positioning system (GPS) receiver associated with the mobile unit. Each directory number may be associated with a different level of services, with corresponding pricing differences, for example.